468 



NOTES AND MEMORANDA. 



of tlie bottom of the well. The threads of this screw are forty-eight 

 to the inch, and the circumference of its head is divided into fifty equal 

 parts. 



Fig. 2 represents the tripod seen from below, showing the ivory 

 points 1, 2, 3, 4, 5, the brass plate A, and the blade K fastened by 

 the clamps m and n. 



Fig. 3 shows the shape of the heads of the bolts 8 and 9, Fig. 1, 

 and the manner in which they are let into the plate A. 

 Fig. 4. 



_J5j 



Fig. 4 represents a section through the pan, showing the arrange- 

 ment of the well W, clamp L, and screw for raising the pan. H is 

 a rubber tube, leading from the bottom of the well, for drawing off 

 the alcohol in the pan after using the instrument. 



Fig. 5. 



Fig. 5 represents the frame X X seen from below, showing the 

 pan, well W, screw F, rubber tube H, and brass guide-pieces, and the 

 manner in which they are attached to the frame. 



